Heart Study Guide Flashcards
How much of the hearts mass of lying to the left of the body’s midline?
2/3s
What is an easy representation of the hearts size?
Size of a closed fist
The inferior angle (pointed end) of the heart is the?
Apex
Name the anatomical region that the heart is within, which also includes all visceral organs within the thoracic cavity excluding the lungs?
Mediastinum
Name the membrane that surrounds and protects the heart. It had two parts.
Pericardium, fibrous and serous parts
The serous parts of the pericardium has a partial and visceral layer. Name this membrane layer that adheres tightly to the surface of the heart.
Epicardium
Between the parietal and visceral layers of pericardium is a cavity and fluid, what are they called and what does it do?
Pericardial fluid, reduces friction between beat.
Name the 3 layers of the heart wall.
Epicardium (outer) myocardium (middle) endocardium (inner)
State the thin transparent outer layer of the heart wall previously mentioned.
Epicardium
Name the heart wall layer that constitutes the bulk of the heart, consisting of cardiac tissue, and is found only in the heart with a special structure and function.
Myocardium
True or false: cardiac muscle fibers do not form into separate networks.
False
How many times longer do cardiac muscle fibers contract over skeletal muscle fibers?
10-15 times longer of a contraction
Name the thin layer of simple squamous epithelium that lines the inside of the myocardium (chambers) and covers the valves and tendons attaches to the valves.
Endocardium
How many chambers does the heart have ?
4
Two upper chambers (“entry wall”) are known as what?
Atria
Two lower chambers (“little bellies”) are known as what?
Ventricles
Between the two upper chambers is a thin partition, what is it called?
Interatrial septum
A preliminary feature of this dividing septum is called? What is it remnant of?
Fossa ovalis, remnant of foreman oval ( opening of baby heart-non functioning lungs in utero)
What separates the right and left ventricles of the heart?
Interventricular septum